U.S. patent application number 15/598381 was filed with the patent office on 2018-01-25 for lower vehicle-body structure of automotive vehicle.
This patent application is currently assigned to MAZDA MOTOR CORPORATION. The applicant listed for this patent is MAZDA MOTOR CORPORATION. Invention is credited to Kazuhiro KAGEYAMA, Junichi TANAKA.
Application Number | 20180022389 15/598381 |
Document ID | / |
Family ID | 60889925 |
Filed Date | 2018-01-25 |
United States Patent
Application |
20180022389 |
Kind Code |
A1 |
KAGEYAMA; Kazuhiro ; et
al. |
January 25, 2018 |
LOWER VEHICLE-BODY STRUCTURE OF AUTOMOTIVE VEHICLE
Abstract
An auxiliary device is provided in a space below a portion of a
floor panel which is positioned between a floor frame and a tunnel
side member which extend in a longitudinal direction, members which
extend in a vehicle width direction and straddle the floor frame
which is positioned on the side of the auxiliary device and a
tunnel side member which is positioned on the opposite side to the
auxiliary device, and a yield strength of the vehicle width
direction of tunnel corresponding portions, in a width direction,
of the members which correspond to a tunnel portion is set to be
lower than that of auxiliary-device corresponding portions, in the
width direction, of the members which correspond to the auxiliary
device.
Inventors: |
KAGEYAMA; Kazuhiro;
(Hiroshima-city, JP) ; TANAKA; Junichi;
(Hiroshima-city, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MAZDA MOTOR CORPORATION |
Hiroshima |
|
JP |
|
|
Assignee: |
MAZDA MOTOR CORPORATION
Hiroshima
JP
|
Family ID: |
60889925 |
Appl. No.: |
15/598381 |
Filed: |
May 18, 2017 |
Current U.S.
Class: |
296/187.08 |
Current CPC
Class: |
B62D 21/157 20130101;
B60K 13/04 20130101; B60Y 2306/01 20130101; B62D 25/20 20130101;
B62D 21/16 20130101; B60K 2001/0438 20130101; B60K 1/04 20130101;
B60R 16/04 20130101; B60K 2015/0634 20130101 |
International
Class: |
B62D 21/15 20060101
B62D021/15; B60R 16/04 20060101 B60R016/04; B62D 25/20 20060101
B62D025/20 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 22, 2016 |
JP |
2016-144735 |
Claims
1. A lower vehicle-body structure of an automotive vehicle,
comprising: a floor panel having a tunnel portion which extends in
a longitudinal direction at a center, in a vehicle width direction,
of the vehicle; a pair of right-and-left floor frames provided on a
lower face of the floor panel to interpose the tunnel portion
therebetween; and a pair of right-and-left tunnel side members
extending along the tunnel portion at respective positons which are
located on an outward side, in the vehicle width direction, of the
tunnel portion and on an inward side, in the vehicle width
direction, of the floor frames, wherein an auxiliary device is
provided below a portion of said floor panel which is positioned
between one of said floor frames and one of said tunnel side
members, a member which extends in the vehicle width direction and
straddles said one of the floor frames and the other tunnel side
member which is opposite to said one of the tunnel side members is
attached, and a yield strength of the vehicle width direction of a
tunnel corresponding portion, in a width direction, of said member
which corresponds to the tunnel portion is set to be lower than
that of an auxiliary-device corresponding portion, in the width
direction, of said member which corresponds to the auxiliary
device.
2. The lower vehicle-body structure of the automotive vehicle of
claim 1, wherein said member is configured such that said tunnel
corresponding portion and said auxiliary-device corresponding
portion are integrated, and the auxiliary-device corresponding
portion has a greater width, in the longitudinal direction, than
the tunnel corresponding portion.
3. The lower vehicle-body structure of the automotive vehicle of
claim 2, wherein said tunnel corresponding portion of the member
has a constricted portion which is configured such that an inward
side, in the vehicle width direction, thereof has a narrower width,
in the longitudinal direction, than an outward side, in the vehicle
width direction, thereof, said auxiliary-device corresponding
portion of the member is configured to substantially linearly
extend along the vehicle width direction, and said member is
attached such that the auxiliary-device corresponding portion is
offset toward said constricted portion of the tunnel corresponding
portion in the longitudinal direction.
4. The lower vehicle-body structure of the automotive vehicle of
claim 3, wherein said auxiliary device is provided on either a
right side or a left side of said tunnel portion, and an end
portion of said member is connected to said other tunnel side
member.
5. The lower vehicle-body structure of the automotive vehicle of
claim 2, wherein said auxiliary device is provided on either a
right side or a left side of said tunnel portion, and an end
portion of said member is connected to said other tunnel side
member.
6. The lower vehicle-body structure of the automotive vehicle of
claim 1, wherein said tunnel corresponding portion of the member
has a constricted portion which is configured such that an inward
side, in the vehicle width direction, thereof has a narrower width,
in the longitudinal direction, than an outward side, in the vehicle
width direction, thereof, said auxiliary-device corresponding
portion of the member is configured to substantially linearly
extend along the vehicle width direction, and said member is
attached such that the auxiliary-device corresponding portion is
offset toward said constricted portion of the tunnel corresponding
portion in the longitudinal direction.
7. The lower vehicle-body structure of the automotive vehicle of
claim 1, wherein said auxiliary device is provided on either a
right side or a left side of said tunnel portion, and an end
portion of said member is connected to said other tunnel side
member.
8. A lower vehicle-body structure of an automotive vehicle,
comprising: a floor panel having a tunnel portion which extends in
a longitudinal direction at a center, in a vehicle width direction,
of the vehicle; a pair of right-and-left floor frames provided on a
lower face of the floor panel to interpose the tunnel portion
therebetween; and a pair of right-and-left tunnel side members
extending along the tunnel portion at respective positons which are
located on an outward side, in the vehicle width direction, of the
tunnel portion and on an inward side, in the vehicle width
direction, of the floor frames, wherein an auxiliary device is
provided below a portion of said floor panel which is positioned
between one of said floor frames and one of said tunnel side
members, a member which extends in the vehicle width direction and
straddles said one of the floor frames and the other tunnel side
member which is opposite to said one of the tunnel side members is
attached, and a yield strength of the vehicle width direction of a
tunnel corresponding portion, in a width direction, of said member
which corresponds to the tunnel portion is set to be lower than
that of an auxiliary-device corresponding portion, in the width
direction, of said member which corresponds to the auxiliary
device, said member is configured such that said tunnel
corresponding portion and said auxiliary-device corresponding
portion are integrated, and the auxiliary-device corresponding
portion has a greater width, in the longitudinal direction, than
the tunnel corresponding portion, said tunnel corresponding portion
of the member has a constricted portion which is configured such
that an inward side, in the vehicle width direction, thereof has a
narrower width, in the longitudinal direction, than an outward
side, in the vehicle width direction, thereof, said
auxiliary-device corresponding portion of the member is configured
to substantially linearly extend along the vehicle width direction,
and said member is attached such that the auxiliary-device
corresponding portion is offset toward said constricted portion of
the tunnel corresponding portion in the longitudinal direction,
said auxiliary device is provided on either a right side or a left
side of said tunnel portion, and an end portion of said member is
connected to said other tunnel side member.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a lower vehicle-body
structure of an automotive vehicle in which an auxiliary device,
such as a battery, is provided below a floor panel.
[0002] US Patent Application Publication No. 2015/0107921 A1 and
Japanese Patent Laid-Open publication No. H09-272400 are known as
the structure in which the auxiliary device, such as the battery,
is provided below the floor panel. The first patent document
discloses the structure in which a battery module as the auxiliary
device is provided below the floor panel in an area which is
enclosed by a floor flame and a tunnel frame (tunnel side member),
which are respectively provided to extend in a longitudinal
direction as a vehicle-body rigidity member at each side of
right-and-left both sides of the floor panel, and front-and-rear
seat cross members, which are respectively provided to extend in a
vehicle width direction as the vehicle-body rigidity member.
[0003] That is, the battery module disclosed in the above-described
first patent document is protected by being provided at the floor
panel such that it is enclosed by the above-described vehicle-body
rigidity members in a vehicle bottom view.
[0004] In the structure disclosed in the first patent document,
however, since no vehicle-body rigidity member extending in the
vehicle width direction is provided at a portion which corresponds
to the battery module in the vehicle bottom view, such as a portion
located below the battery module, there was still room for
improvement in protection of the battery module against a vehicle
side collision (side face collision) or the like.
[0005] The second patent document discloses the structure in which
plural batteries as the auxiliary device are provided below the
floor panel to extend in the vehicle width direction, a storage box
which stores the batteries therein is attached so as to straddle a
fixation portion (a tunnel portion), this battery storage box is
composed of a roughly rectangular-shaped bottom portion which
covers the batteries from below and a frame portion which is
configured to rise upward from four sides of this bottom portion,
and a whole part of the batteries provided below the floor panel
are covered with the battery storage box from outside.
[0006] In the structure disclosed in the second patent document,
however, while the protection performance of the batteries is
improved because the batteries are protected with the hard storage
box, there was room for improvement in achieving a light weight of
a vehicle body.
SUMMARY OF THE INVENTION
[0007] Accordingly, an object of the present invention is to
provide a lower vehicle-body 3 structure of an automotive vehicle
which can properly protect the auxiliary device from the severe
vehicle side collision, such as a pole collision, without
accompanying an improper weight increase of the vehicle.
[0008] The present invention is a lower vehicle-body structure of
an automotive vehicle, comprising a floor panel having a tunnel
portion which extends in a longitudinal direction at a center, in a
vehicle width direction, of the vehicle, a pair of right-and-left
floor frames provided on a lower face of the floor panel to
interpose the tunnel portion therebetween, and a pair of
right-and-left tunnel side members extending along the tunnel
portion at respective positons which are located on an outward
side, in the vehicle width direction, of the tunnel portion and on
an inward side, in the vehicle width direction, of the floor
frames, wherein an auxiliary device is provided below a portion of
said floor panel which is positioned between one of said floor
frames and one of said tunnel side members, a member which extends
in the vehicle width direction and straddles said one of the floor
frames and the other tunnel side member which is opposite to said
one of the tunnel side members is attached, and a yield strength of
the vehicle width direction of a tunnel corresponding portion, in a
width direction, of said member which corresponds to the tunnel
portion is set to be lower than that of an auxiliary-device
corresponding portion, in the width direction, of said member which
corresponds to the auxiliary device.
[0009] According to the present invention, a vehicle-side-collision
load can be directly transmitted to the opposite-side tunnel side
member by way of the above-described member and also the tunnel
portion can be deformed properly for load absorption, thereby
preventing the auxiliary device from being deformed.
[0010] In an embodiment of the present invention, the member is
configured such that the tunnel corresponding portion and the
auxiliary-device corresponding portion are integrated, and the
auxiliary-device corresponding portion has a greater width, in the
longitudinal direction, than the tunnel corresponding portion.
[0011] According to this embodiment, the vehicle height can be
prevented from being improperly low and also the productivity of
the above-described member and the covering performance of the
auxiliary device can be improved.
[0012] In another embodiment of the present invention, the tunnel
corresponding portion of the member has a constricted portion which
is configured such that an inward side, in the vehicle width
direction, thereof has a narrower width, in the longitudinal
direction, than an outward side, in the vehicle width direction,
thereof, the auxiliary-device corresponding portion of the member
is configured to substantially linearly extend along the vehicle
width direction, and the member is attached such that the
auxiliary-device corresponding portion is offset toward the
constricted portion of the tunnel corresponding portion in the
longitudinal direction.
[0013] According to this embodiment, increasing of the amount of
load absorption by the load absorption deformation of the tunnel
portion and reinforcing of the vehicle body can be compatibly
attained at a high level.
[0014] In another embodiment of the present invention, the
auxiliary device is arranged on either a right side or a left side
of the tunnel portion, and an end portion of the member is
connected to the other tunnel side member.
[0015] According to this embodiment, the vehicle-side-collision
load can be prevented from being transmitted to an auxiliary-device
arrangement portion from a side which is opposite relatively to the
tunnel portion, in the vehicle width direction, to a side having
the auxiliary-device arrangement portion.
[0016] Other features, aspects, and advantages of the present
invention will become apparent from the following description which
refers to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a bottom view of a lower vehicle-body structure of
an automotive vehicle of a present embodiment.
[0018] FIG. 2 is an enlarged view of a major part of FIG. 1.
[0019] FIG. 3 is a perspective sectional view taken along line A-A
of a major part of FIG. 1.
[0020] FIG. 4 is a longitudinal sectional view showing a major part
of a central portion, in a width direction, of a tunnel
portion.
[0021] FIGS. 5A and 5B are explanatory diagrams of structures of a
rear underfloor member and a rear cross member.
[0022] FIGS. 6A, 6B and 6C are explanatory diagrams of a structure
of a front underfloor member.
[0023] FIG. 7 is an explanatory diagram of the structure of the
rear underfloor member.
[0024] FIGS. 8A and 8B are explanatory diagrams of operations of
the front and rear underfloor members in a vehicle side
collision.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Hereafter, an embodiment of the present invention will be
described specifically referring to the accompanying drawings. FIG.
1 is a bottom view of a lower vehicle-body structure of an
automotive vehicle of the present embodiment, FIG. 2 is an enlarged
view of a major part of FIG. 1, FIG. 3 is a perspective sectional
view taken along line A-A of a major part of FIG. 1, FIG. 4 is a
longitudinal sectional view showing a major part of a central
portion, in a width direction, of a tunnel portion, FIG. 5A is a
perspective sectional view taken along line B-B of a major part of
FIG. 1, when viewed from obliquely above, FIG. 5B is a perspective
sectional view taken along line C-C of a major part of FIG. 1, FIG.
6A is a perspective view of an upper panel of a front underfloor
member, when viewed from obliquely forward and upward sides, FIG.
6B is an enlarged sectional view of the front underfloor member,
taken along line D-D of FIG. 6A, FIG. 6C is an enlarged sectional
view of the front underfloor member, taken along line E-E of FIG.
6A, FIG. 7 is a perspective view of an upper panel of a rear
underfloor member, when viewed from obliquely forward and upward
sides, FIG. 8A is an explanatory diagram of an operation of the
front underfloor member when a large load is inputted to the front
underfloor member from a vehicle right side in a vehicle side (side
face) collision, and FIG. 8B is an explanatory diagram of an
operation of the rear underfloor member when the large load is
inputted to the rear underfloor member from the vehicle right side
in the vehicle side collision.
[0026] In the figures, an arrow F shows a vehicle forward side, an
arrow R shows a vehicle rightward side, an arrow L shows a vehicle
leftward side, and an arrow U shows a vehicle upward side. Further,
the forward, rearward, leftward, rightward, upward and downward
sides which will be used in describing the front and rear
underfloor members below mean the respective directional sides in a
state where the front and rear underfloor members are installed to
the vehicle, which are the same as the forward, rearward, leftward,
rightward, upward and downward sides of the vehicle,
respectively.
[0027] As shown in FIGS. 1-3, the lower vehicle-body structure of
the automotive vehicle of the present embodiment comprises a floor
panel 4, a pair of right-and-left side sills 5 (5a, 5b ), a dash
panel 6, a pair of right-and-left front side frames 7 (7a, 76b), a
pair of right-and-left tunnel side members 8 (8a, 8b ), a pair of
right-and-left floor frames 9 (9a, 9b) (B frame), front and rear
underfloor members 2, 3 and others.
[0028] As shown in FIG. 3, the floor panel 4, which forms a floor
face, is configured such that a tunnel portion 4a which extends in
the vehicle longitudinal direction at a central portion, in the
vehicle width direction, of the floor panel 4 protrudes upward (a
cabin side) in a convex shape.
[0029] As shown in FIG. 3, the pair of right-and-left side sills
5a, 5b extend in the vehicle longitudinal direction, and the floor
panel 4 is joined to these side sills 5a, 5b at its right-and-left
end portions. Each of the side sills 5a, 5b comprises an inner
panel 51 and an outer panel 52 which have a hat-shaped cross
section, respectively, and a closed cross section extending in the
vehicle longitudinal direction is formed by these inner panel 51
and outer panel 52. The side sill 5 further comprises a
reinforcement 53 which is positioned inside the closed cross
section between the inner panel 51 and the outer panel 52.
[0030] Further, an outward end, in the vehicle width direction, of
the floor panel 4 is joined to a lower portion of an inward side,
in the vehicle width direction, of the inner panel 51.
[0031] The dash panel 6 partitions the cabin from an engine room
which is provided at a vehicle front side, and a front end portion
of the floor panel 4 is joined to a lower end portion of the dash
panel 6 which extends obliquely rearward and downward.
[0032] The pair of right-and-left front side frames 7a, 7b extend
in the vehicle longitudinal direction, and their rear portions are
joined to a lower face of the floor panel 4, so that a closed cross
section is formed by a rear portion of the front side frame 7 and a
lower face of the floor panel 4. Further, a forward-side portion of
the rear portion of the front side frame 7 which is positioned in
front of its joint portion to the floor panel 4 is joined to a
front face portion of the dash panel 6 (see FIG. 1).
[0033] The pair of right-and-left front side frames 8a, 8b (tunnel
lower frames) are configured such that their front portions extend
obliquely inward and rearward from respective inward-side faces of
the rear end portions of the front side frames 7a, 7b, respective
portions which are positioned in back of the above-described
obliquely-extending portions are provided adjacently to both sides,
in the vehicle width direction, of the tunnel portion 4a and
configured to be respective convex hat-shaped portions which extend
in the vehicle longitudinal direction roughly linearly and protrude
downward, and they are joined to the lower portion of the dash
panel 6 and the lower face of the floor panel 4 so as to form
respective closed cross sections extending in the longitudinal
direction. In FIG. 3, reference character 110 denotes a tunnel
reinforcing member which is configured to have a hat-shaped cross
section which protrudes upward in a convex shape and also form a
closed cross section together with an upper face of the tunnel
portion 4a.
[0034] Further, as shown in FIGS. 1 and 2, a front tunnel cross
member 100 and a rear tunnel cross member 101 which reinforce the
tunnel portion 4a are arranged at front and rear sides of a central
portion, in the longitudinal direction, of the tunnel portion 4a.
These front and rear tunnel cross members 100, 101 are provided to
straddle the tunnel portion 4a and protrude upward along an inner
face of the tunnel portion 4a, and joined to the inner face (lower
face) of the tunnel portion 4a as shown in FIG. 4.
[0035] Herein, the tunnel portion 4a is configured such that its
level becomes gradually lower toward its rear side as shown in FIG.
4. That is, the tunnel portion 4a is configured such that an inner
space formed thereby becomes narrower toward its rear side. In this
inner space formed by the tunnel portion 4a, a propeller shaft, not
illustrated, which extends from a vehicle forward side to a vehicle
rearward side, an exhaust pipe as an engine exhaust-system parts,
and others are arranged in the longitudinal direction.
[0036] The pair of right-and-left floor frames 9a, 9b are
configured to be respective convex hat-shaped portions which extend
rearward from rear ends of the front side frames 7a, 7b and
protrude downward on the lower face of the floor panel 4, and they
are joined to the lower portion of the dash panel 6 and the lower
face of the floor panel 4 so as to form respective closed cross
sections. These floor frames 9a, 9b respectively extend obliquely
outward and rearward in each area between the side sill 5 and the
tunnel side member 8.
[0037] Herein, rear ends of the floor frames 9a, 9b are joined to
respective inward faces of the rear portions of the side sills 5
and respective front ends of the rear side frames 111 which extend
rearward (see FIG. 1).
[0038] In FIG. 1, reference character 112 denotes a pair of
right-and-left torque boxes as a reinforcing member, and cross
members 113 which interconnects respective front portions of the
side sills 5 and respective front portions of the front frames 9
are arranged on the lower face of the floor panel 4 in back of the
torque box 112.
[0039] Further, as shown in FIG. 3, a front seat 200 (front seat)
is provided on a front portion of the floor panel 41, which is
supported via a seat rail 201 so as to slide longitudinally.
[0040] The front seat 200 comprises a pair of right-and-left seats
(a driver's seat and a passenger seat (assistant driver's seat))
which are arranged side by side in the vehicle width direction.
Herein, a rear seat is provided on a rear portion of the floor
panel 41 which is positioned in back of the front seat 200, which
is not illustrated in the present embodiment.
[0041] As shown in FIGS. 3 and 5B, the seat rail 201 comprises a
pair of right-and-left rails which are positioned on both sides of
each front seat 200, which are supported at a front cross member
210 and a rear cross member 211, extending in the longitudinal
direction.
[0042] The front cross member 210 and the rear cross member 211 are
provided, on each side of the vehicle right-and-left sides, to
extend in the vehicle width direction at respective positions on
the upper face of the floor panel 4 which correspond to front and
rear sides of the front seat 200, and respective outward ends, in
the vehicle width direction, of these cross members 210, 211 are
connected to the side sill 5 and respective inward ends, in the
vehicle width direction, of these cross members 210, 211 are
connected to the tunnel side member 8, thereby forming respective
closed cross sections between the upper face of the floor panel 4
and them. The front cross member 210 is arranged at a position, in
the longitudinal direction, of the floor panel 4 which roughly
corresponds to a front underfloor member 2 which is provided on the
lower face of the floor panel 4, which will be described later, and
the rear cross member 211 is arranged at a position, in the
longitudinal direction, of the floor panel 4 which roughly
corresponds to a rear underfloor member 3 which is provided on the
lower face of the floor panel 4, which will be described later. A
cabin-inside space for the vehicle side collision is secured by
these cross members 210, 211 and these underfloor members 2, 3.
[0043] Specifically, a front end of the seat rail 201 is, as shown
in FIG. 3, attached such that it is directly supported at the front
cross member 210, whereas a rear portion of the seat rail 201 is,
as shown in FIGS. 5A and 5B, attached to the rear cross member 211
via a seat support bracket 212. The seat support bracket 212 is
provided at both end portions, in the vehicle width direction, of
the rear cross member 211. Herein, illustration of the seat rail
201 is omitted in FIG. 5A.
[0044] As shown in FIGS. 1-3, 5A and 5B, according to the
above-described lower vehicle-body structure, a power storage unit
40 as an auxiliary device is provided below the floor panel 4 on
one side, in the vehicle width direction, of the vehicle,
specifically in the present embodiment, provided in an underfloor
space between the right floor flame 9a and the right tunnel side
member 8a. The power storage unit 40 is configured such that its
casing is properly attached to the lower face of the floor panel 4
or the front-and-rear underfloor members 2, 3 or the like by means
of bolts or the like, not illustrated.
[0045] Herein, any other auxiliary device, such as an electric
device, for example, a fuel tank, an exhaust gas purifier (a
so-called SCR), a vehicle control unit, a noncontact charge unit,
or a drive recorder, is applicable as the above-described auxiliary
device in place of the power storage unit 40. Meanwhile, as shown
in FIG. 1, no auxiliary device, such as the power storage device,
is provided below the floor panel 4 on the other side, in the
vehicle width direction, of the vehicle, i.e., on the left side of
the vehicle in the present embodiment.
[0046] The power storage unit 40 is arranged in a
power-storage-unit arrangement space S between the left floor frame
9a and the tunnel side member 8a, and configured in a
roughly-rectangular shape, in the bottom view, such that its front
end roughly corresponds to a position, in the longitudinal
direction, of the cross member 113 (see FIG. 1) and its rear end
roughly corresponds to a position, in the longitudinal direction,
of the rear tunnel cross member 101 (see FIG. 1, 5A and 5B).
[0047] Herein, by arranging the power storage unit 40 between the
floor frame 9a and the tunnel side member 8a on the right side, in
the vehicle width direction, of the vehicle, the space between the
side sill 5a and the floor frame 9a is deformed first when the
vehicle has a side collision from the vehicle right side, thereby
absorbing the vehicle-side-collision load. Thus, the
power-storage-unit arrangement space S can be protected so as not
to be deformed by the vehicle-side-collision load.
[0048] As shown in FIGS. 1 and 3, a gusset 41 which covers the
power storage unit 40 from below is provided below the floor panel
4 and at a middle position, in the longitudinal direction, of the
power storage unit 40. This gusset 41 is configured to extend in
the vehicle width direction, and connected to the right floor frame
9a and the right tunnel side member 8a.
[0049] Further, the underfloor members 2, 3 which respectively
extend in the vehicle width direction and cover the power storage
unit 40 from below are attached to front and rear sides, in the
longitudinal direction, of the power storage unit 40 relatively to
the gusset 41 below the floor panel 4. The underfloor members 2, 3
comprise the front underfloor member 2 and the rear underfloor
member 3 which is arranged in back of the front underfloor member
2.
[0050] While the gusset 41 is configured to be laid between the
right floor frame 9a and the right tunnel side member 8a, each of
these underfloor members 2, 3 is configured to be laid between the
right floor frame 9a where the power storage unit 40 is provided
and the left tunnel side member 9b which is provided on the
opposite side to arrangement of the power storage unit 40.
[0051] That is, the front and rear underfloor members 2, 3 are
respectively provided from the right side of the tunnel portion 4a
where the power storage unit 40 is provided to the opposite-side
(left-side) tunnel side member 8b, and respective left end portions
2b, 3b of the underfloor members 2, 3 are connected to the left
tunnel side member 8b. Herein, the respective underfloor members 2,
3 are configured not to extend leftward (outward in the vehicle
width direction) beyond the left tunnel side member 8b.
[0052] The front and rear underfloor members 2, 3 respectively
extend linearly in the vehicle width direction, and respectively
comprise front and rear tunnel corresponding portions 21, 31 which
extend so as to mainly straddle the tunnel portion 4a in the
vehicle width direction and front and rear auxiliary-device
corresponding portions 22, 32 which extend so as to mainly straddle
the power storage unit 40 as the auxiliary device, which are
integrated.
[0053] The front underfloor member 2 is configured such that the
front tunnel corresponding portion 21 is narrower, in the
longitudinal direction, than the front auxiliary-device
corresponding portion 22. Thereby, a yield strength of the vehicle
width direction of the front tunnel corresponding portion 21 is set
to be lower than that of the front auxiliary-device corresponding
portion 22. Herein, the above-described yield strength of the
vehicle width direction means the yield strength against the
vehicle-side-collision load. In other words, since the front
underfloor member 2 is configured such that the auxiliary-device
corresponding portion 22 is wider, in the longitudinal direction,
than the front tunnel corresponding portion 21, the covering
performance (chipping-proof performance) that chipping (flying
stones) for the power storage unit 40 is properly prevented is
improved.
[0054] As shown in FIGS. 3, 4, 6A, 6B and 6C, the front underfloor
member 2 comprises an upper panel 23 and a lower panel 24 which are
provided to face each other vertically, and the front
auxiliary-device corresponding portion 22 is arranged so as to
cover a roughly central portion, in the longitudinal direction, of
the power storage unit 40 from below and the front tunnel
corresponding portion 21 is arranged so as to overlap, in the
longitudinal direction, the front tunnel cross member 100 at the
tunnel portion 4a (see FIGS. 1 and 2). As shown in FIGS. 2, 3, 6A,
6B and 6C, the upper panel 23 and the lower panel 24 of the front
underfloor member 2 are configured such that they have similar
shapes and sizes in the bottom view.
[0055] Subsequently, attachments of the front underfloor member 2
to the respective vehicle-body side frames 9a, 8a, 8b provided
below the floor panel 4 will be described referring to FIGS. 2, 6
and 8a. The above-described front underfloor member 2 is configured
such that the upper panel 23 and the lower panel 24 are fastened
together to a lower face of the right front frame 9a at front and
rear positions of its right end by using bolts B1 and nuts N1 or
the like, thereby forming a right-end fastening portion 25a.
[0056] The above-described front underfloor member 2 is configured
such that the upper panel 23 and the lower panel 24 are fastened
together to a lower face of the left tunnel side member 8b at front
and rear positions of its left end portion 2b by using bolts B2 and
nuts N2 or the like, thereby forming a left-end fastening portion
25b.
[0057] Further, the above-described front underfloor member 2 is
configured such that the upper panel 23 and the lower panel 24 are
fastened together to a lower face of the right tunnel side member
8a at a middle position, in the vehicle width direction, thereof
which corresponds to a position where the front underfloor member 2
straddles the right tunnel side member 8a by using bolts B3 and
nuts N3 or the like, thereby forming a middle fastening portion
25c.
[0058] Thus, the right floor frame 9a and the right tunnel side
member 8a are connected via the front auxiliary-device
corresponding portion 22 of the front underfloor member 2, and the
pair of right-and-left tunnel side members 8a, 8b are connected via
the front tunnel corresponding portion 21. Herein, the front
underfloor member 2 is configured not to extend leftward (outward
in the vehicle width direction) beyond the left tunnel side member
8b (see FIGS. 1-3).
[0059] In the present embodiment, as shown in FIG. 2, a wide
portion, in the longitudinal direction, of the front underfloor
member 2, including not only a portion, in the vehicle width
direction, thereof which corresponds to the power storage unit 40
but the right end portion 2a and the middle portion 2c (the
connection portion 2c of the front tunnel corresponding portion 21
and the front auxiliary-device corresponding portion 22), is set to
be the front auxiliary-device corresponding portion 22, and another
portion of the front underfloor member 2, including not only a
portion, in the vehicle width direction, thereof which corresponds
to the tunnel portion 4a but the left end portion 2b and the middle
portion 2c of the front underfloor member 2, is set to be the front
tunnel corresponding portion 21.
[0060] As shown in FIGS. 2, 6B and 6C, the lower panel 24 of the
front underfloor member 2 has a middle convex portion 27a which
extends in the vehicle width direction and protrudes downward at a
central portion, in a longitudinal direction, thereof over a range
from the front auxiliary-device corresponding portion 22 to the
front tunnel corresponding portion 21. Further, the lower panel 24
of the front auxiliary-device corresponding portion 22 has a pair
of concave portions 27b in front and rear of the middle convex
portion 27a, so that the lower panel 24 of the front
auxiliary-device corresponding portion 22 is configured to have an
uneven-shaped cross section which is perpendicular to the vehicle
width direction. Thus, the front auxiliary-device corresponding
portion 22 is configured to have a wider width, in the longitudinal
direction, than the front tunnel corresponding portion 21.
[0061] However, as shown in FIGS. 2 and 6B, front and rear portions
of a left end portion 2b of the front tunnel corresponding portion
21 are respectively configured to have a wide width in accordance
with its being formed in a flange shape so as to correspond to the
left-end fastening portion 25b. Meanwhile, the right end portion 2c
of the front tunnel corresponding portion 21, which corresponds to
the connection portion 2c of the front tunnel corresponding portion
21 and the front auxiliary-device corresponding portion 22, is
configured to have the same width as the front auxiliary-device
corresponding portion 22.
[0062] That is, a portion of the front tunnel corresponding portion
21 which excludes its right and left both end portions 2b, 2c has a
width which is equivalent to or smaller than a distance between the
front and rear sides of the right-end fastening portion 25a
provided at the right end portion 2a of the front underfloor member
2, a distance between the front and rear sides of the left-end
fastening portion 25b provided at the left end portion 2a of the
front underfloor member 2, or a distance between the front and rear
sides of the middle fastening portion 25c provided at the middle
portion 2c of the front underfloor member 2.
[0063] As shown in FIG. 6B, the lower panel 24 of the front
auxiliary-device corresponding portion 22 comprises a middle lower
wall portion 24a which is horizontally positioned below a middle,
in the longitudinal direction, thereof, a pair of inward-side
vertical wall portions 24b, 24b which rise from front and rear ends
of the middle lower wall portion 24a, a pair of upper wall portions
24c, 24c which horizontally extend outward (forward and rearward)
from respective upper ends of the inward-side vertical wall
portions 24b, a pair of outward-side vertical wall portions 24d,
24d which lower (i.e., extend downward) from front and rear ends of
the upper wall portions 24c, and a pair of outward-side lower wall
portions 24e, 24e which extend horizontally outward (forward and
rearward) from respective lower ends of the outward-side vertical
wall portions 24d, which are integrated.
[0064] Upper faces of the pair of upper wall portions 24c, 24c are
joined to a lower face of the upper panel 23, the above-described
middle convex portion 27a is formed by the middle lower wall
portion 24a and the pair of upper wall portions 24b, 24b, and a
closed cross section is formed between the middle convex portion
27a and the upper panel 23.
[0065] Meanwhile, as shown in FIG. 6C, the lower panel 24 of the
front tunnel corresponding portion 21 also has a middle convex
portion 27a which is formed by the middle lower wall portion 24a
and the pair of inward-side vertical wall portions 24b, 24b, and a
closed cross section is formed between the middle convex portion
27a and the upper panel 23. Herein, the upper wall portion 24c of
the front tunnel corresponding portion 21 is configured to be one
half of or shorter than the length of the upper wall portion 24c of
the front auxiliary-device corresponding portion 22.
[0066] Herein, as shown in FIGS. 6A and 8A, the lower panel 24 and
the upper panel 23 of the front underfloor member 2 are configured
such that the front tunnel corresponding portion 21 is arranged to
be upward offset from the front auxiliary-device corresponding
portion 22 by substantially a plate thickness of the front
auxiliary-device corresponding portion 22, including the connection
portion 2c to the front auxiliary-device corresponding portion 22,
and a step portion 21d is formed at a right end of the connection
portion 2c of the front tunnel corresponding portion 21 and the
front auxiliary-device corresponding portion 22 (see FIG. 6).
Moreover, plural seat portions 21e which protrude substantially up
to a level (height) position of the upper face of the front tunnel
portion 21 are formed at a portion of the front auxiliary-device
corresponding portion 22 which corresponds to at least the
right-end fastening portion 25a. Herein, a penetration hole 21f for
penetration of the bolt B1 is formed at a central portion of the
seat portion 21e which is provided at the right-end fastening
portion 25a (see FIG. 6A).
[0067] The above-described front underfloor member 2 which has been
attached to the respective frames 9a, 8a, 8b positioned below the
floor panel 4 as described above from below can be arranged as
shown in FIG. 8A such that some portions of the front underfloor
member 2 which correspond to at least the right-end fastening
portion 25a, the left-end fastening portion 25b, and the middle
fastening portion 25c are located at a higher level (height) than
the other portion of the front underfloor member 2.
[0068] That is, as shown in FIG. 8A, the middle fastening portion
25c and the left-end fastening portion 25b are respectively
fastened to the right tunnel side member 8a and the left tunnel
member 8b in such a manner that the height (level) H1 of the
fastening potions 25c, 25b is higher than the height (level) H2 of
a rigidity center g (gravity center) which is located at a central
position, in the vehicle width direction, of the front tunnel
corresponding portion 21.
[0069] Thereby, even if the vehicle-side-collision load which is
large enough to deform the front underfloor member 2 itself is
inputted to the front underfloor member 2 from the vehicle-body
rightward side, the front tunnel corresponding portion 21 which is
configured to have the narrow-wide portion so as to be weaker (a
yield strength of the vehicle width direction of the front tunnel
corresponding portion 21 is lower) than the front auxiliary-device
corresponding portion 22 is deformed with priority. Moreover, when
the front tunnel corresponding portion 21 is deformed, the front
tunnel corresponding portion 21 can be deformed downward securely,
so that the deformed front tunnel corresponding portion 21 can be
prevented from interfering with an exhaust pipe and others, not
illustrated, which are arranged in the tunnel portion 4a.
[0070] Specifically, since the middle fastening portion 25c and the
left-end fastening portion 25b are fastened to the respective
tunnel side members 8a, 8b provided below the floor panel 4 at the
relatively high level (H1), compared with the other portion of the
front underfloor member 2, the load inputted to the middle
fastening portion 25c and the left-end fastening portion 25b from
the front auxiliary-device corresponding portion 22 which is
arranged at the relatively low level (H2) via the step portion 21d
is transmitted, being offset upward. Further, since a load input
point of the vehicle-side-collision load inputted to the middle
fastening portion 25c and the left-end fastening portion 25b is
positioned above the rigidity center g of the front tunnel
corresponding portion 21 (H1>H2), the front tunnel portion 4a is
compressed inward in the vehicle width direction by the load input
to the middle fastening portion 25c and the left-end fastening
portion 25b, so that the front tunnel corresponding portion 21 can
be deformed downward securely as shown by an imaginary line in FIG.
8A.
[0071] Accordingly, it can be prevented that the front tunnel
corresponding portion 21 which may be bent upward, for example,
comes to interfere with the exhaust pipe and others arranged in the
tunnel portion 4a and its deformation is blocked, thereby damaging
the load absorption performance.
[0072] Subsequently, the above-described rear underfloor member 3
will be described referring to FIG. 2. The rear auxiliary-device
corresponding portion 32 of the rear underfloor member 3 has
substantially the same longitudinal-directional width as the front
auxiliary-device corresponding portion 22 of the front underfloor
member 2 and is configured to be linear in the vehicle width
direction. Meanwhile, the rear tunnel corresponding portion 31 of
the rear underfloor member 3 has a longitudinal-directional narrow
portion 38 (a constricted portion 38) which is configured such that
a middle part, in the vehicle width direction, of the rear tunnel
corresponding portion 31 is narrower than outward portions, in the
vehicle width direction, of the rear tunnel corresponding portion
31, and this rear tunnel corresponding portion 31 is configured
such that both apexes of right-and-left isosceles triangles are
butted against each other at a middle portion, in the vehicle width
direction, of the vehicle body, i.e., formed in a so-called
butterfly shape.
[0073] Thus, the rear tunnel corresponding portion 31 has a front
concave apace 39f which is concaved rearward relatively to the
vehicle outward side at a middle portion, in the vehicle width
direction, of a front-side portion of the rear tunnel corresponding
portion 31 and also has a rear concave space 39r which is concaved
forward relatively to the vehicle outward side at a middle portion,
in the vehicle width direction, of a rear-side portion of the rear
tunnel corresponding portion 31.
[0074] That is, a front side of the rear tunnel corresponding
portion 31 of the rear underfloor member 3 is configured in a
constricted shape (concave shape) such that a central portion, in
the vehicle width direction, thereof is constricted rearward
relatively to the vehicle outward side, so that a front-side
constricted portion 38a is formed at a central portion, in the
vehicle width direction, of this front side. A rear side of the
rear tunnel corresponding portion 31 of the rear underfloor member
3 is configured in another constricted shape (concave shape) such
that the central portion, in the vehicle width direction, thereof
is constricted forward relatively to the vehicle outward side, so
that a rear-side constricted portion 38b is formed at a central
portion, in the vehicle width direction, of this rear side.
[0075] Moreover, the rear underfloor member 3 is configured such
that the rear auxiliary-device corresponding portion 32 is provided
to be offset, in the longitudinal direction, toward the front-side
constricted portion 38a of the rear tunnel corresponding portion
31, and the rear auxiliary-device corresponding portion 32 is
integrally connected to the rear tunnel corresponding portion
31.
[0076] That is, since the rear auxiliary-device corresponding
portion 32 is arranged in an area where it overlaps, in the
longitudinal direction, the front-side constricted portion 38a of
the rear tunnel corresponding portion 31, the front concave apace
39f is provided on a left-side extension line of the rear
auxiliary-device corresponding portion 32 which is configured to
extend linearly in the vehicle width direction. Thereby, the yield
strength of the vehicle width direction of the tunnel corresponding
portion 31 is set to be lower than that of the rear
auxiliary-device corresponding portion 32.
[0077] Subsequently, respective specific shapes of the rear
auxiliary-device corresponding portion 32 and the rear tunnel
corresponding portion 31 will be described. The rear
auxiliary-device corresponding portion 32 is configured to have
substantially the same cross-section shape as the front
auxiliary-device corresponding portion 22 (see FIG. 6A) in the
cross section perpendicular to the vehicle width direction. That
is, as shown in FIG. 2, the rear auxiliary-device corresponding
portion 32 has a middle convex portion 37a which protrudes downward
at a central portion, in the vehicle width direction, thereof and a
pair of concave portions 37b, 37b in front and rear of the middle
convex portion 27a, so that the rear auxiliary-device corresponding
portion 32 is configured to have an uneven-shaped cross section
which is perpendicular to the vehicle width direction, and a closed
cross section which extends in the vehicle width direction is
formed between the lower panel 34 and the upper panel 33.
[0078] Meanwhile, as shown in FIG. 2, the lower panel 34 of the
rear tunnel corresponding portion 32 is formed in a roughly X shape
in the bottom view, and comprises an X-shaped convex portion 31a
which protrudes downward in the roughly X shape in the bottom view
and a flange portion 31b which is formed along an upper edge side
of the X-shaped convex portion 31a, which are formed integrally.
The X-shaped convex portion 31a is formed in the X shape in the
bottom view, which comprises a rightward-forward linear convex
portion 31c which linearly extends obliquely rightward and forward
relatively to the vehicle width direction and a leftward-forward
linear convex portion 31d which linearly extends obliquely leftward
and forward relatively to the vehicle width direction. These linear
convex portions 31c, 31d cross each other at the narrow portion 38
provided at the central portion of the X-shaped convex portion
31a.
[0079] An X-shaped closed cross section is formed inside by the
X-shaped convex portion 31a of the lower panel 34 and the upper
panel 33 which is configured such that part of this panel 33 which
faces the X-shaped convex portion 31a is of a flat shape. Herein, a
right-side concave space 39a is formed on the right side of the
central portion of the X-shaped convex portion 31a of the lower
panel 34, whereas a left-side concave space 39b is formed on the
left side of the central portion of the X-shaped convex portion 31a
of the lower panel 34.
[0080] A left end portion 3cf of the above-described middle convex
portion 37a of the rear auxiliary-device corresponding portion 32
and a right end portion 3cf of the rightward-forward linear convex
portion 31c of the rear tunnel corresponding portion 31 are
connected integrally, and their respective inside
closed-cross-section portions extend continuously.
[0081] As shown in FIG. 7, the upper panel 33 of the rear tunnel
corresponding portion 31 is formed at a portion where it overlaps
the right-side concave space 39a and the left-side concave space
39b of the lower panel 34 in the bottom view, in addition to a
portion where it overlaps the lower panel 34 in the bottom view,
and the upper panel 33 is configured such that both apexes of
isosceles triangles which are arranged on right and left sides are
butted against each other at its middle portion, i.e., formed in
the so-called butterfly shape.
[0082] Further, the upper panel 33 includes protrusion portions 31g
which protrude upward at four portions which exclude the central
portion and both end portions thereof. These protrusion portions
31g are arranged at four positions, in total, which are located in
front and back of a left side and a right side of the upper panel
33, respectively. In other words, a central portion of the upper
panel 33 is configured to be concaved downward relatively to the
four protrusion portions 31g, so that a concave central portion 31e
is formed at an upper face of the central portion, in the plan
view, of the rear tunnel corresponding portion 31.
[0083] Further, as shown in FIG. 2, the rear underfloor member 3 is
configured such that the upper panel 33 and the lower panel 34 are
arranged so as to face each other in the vertical direction and
integrally formed, and the rear auxiliary-device corresponding
portion 3 covers a rear portion of the power storage unit 40. Also,
the front-side concave space 39f of the rear tunnel corresponding
portion 31 is arranged at a position which corresponds to the rear
tunnel cross member 101 in the longitudinal direction, that is, a
position where a central portion of the X-shaped convex portion 31a
is offset rearward from the rear tunnel cross member 101.
[0084] As shown in FIGS. 2 and 8B, the above-described rear
underfloor member 3 is configured such that the upper panel 33 and
the lower panel 34 are fastened together to a lower face of the
right floor frame 9a by bolts B4 and nuts N4 or the like at front
and rear sides of its right end portion 3a, thereby forming a
right-end fastening portion 35a.
[0085] The rear underfloor member 3 is configured such that the
upper panel 33 and the lower panel 34 are fastened together to a
lower face of the left tunnel side member 8 by bolts B5 and nuts N5
or the like at front and rear sides of its left-end fastening
portion 3b (3bf, 3b r), thereby forming a left-end fastening
portion 35b (35b f, 35b r).
[0086] The rear underfloor member 3 is configured such that the
upper panel 33 and the lower panel 34 are fastened together to a
lower face of the right tunnel side member 8b by bolts B6 and nuts
N6 or the like at a middle portion 3c (3cf, 3cr), in the vehicle
width direction, thereof where the rear underfloor 3 straddles the
right tunnel side member 8, thereby forming a middle fastening
portion 35c (35cf, 35cr).
[0087] The right-end fastening portion 35a comprises the front-side
middle-end fastening portion 35cf which is provided at the
connection portion 3cf of the rear auxiliary-device corresponding
portion 32 and the rear tunnel corresponding portion 31 and the
rear-side middle-end fastening portion 35cr which is provided at
the right-rear end portion 3cr of the rear tunnel corresponding
portion 31. Further, the left-end fastening portion 35b comprises
the front-side left-end fastening portion 35b f which is provided
at the left-front end portion 3b f of the rear tunnel corresponding
portion 31 and the rear-side left-end fastening portion 35b r which
is provided at the left-rear end portion 3b r of the rear tunnel
corresponding portion 31.
[0088] Thereby, the right floor frame 9a and the right tunnel side
member 8a are connected via the rear auxiliary-device corresponding
portion 32, and the pair of right-and-left tunnel side members 8a,
8b are connected via the rear tunnel corresponding portion 31.
[0089] Herein, as shown in FIGS. 7 and 8B, the rear underfloor
member 3 is configured, similarly to the front underfloor member 2,
such that the rear tunnel corresponding portion 31 together with
the lower panel 34 and the upper panel 33, including the connection
portion 3cf to the rear auxiliary-device corresponding portion 32,
are offset upward relatively to the rear auxiliary-device
corresponding portion 32 substantially by a plate thickness of the
rear auxiliary-device corresponding portion 32, and a step portion
36b is formed at a right end of the connection portion 3cf (the
front-side middle position 3cf of the rear underfloor member 3) of
the rear tunnel corresponding portion 31 and the rear
auxiliary-device portion 32 (see FIG. 7). Further, plural base
portions 36c which protrude up to a level (height) of the upper
face of the front tunnel portion 4a are provided a portion of the
rear auxiliary-device corresponding portion 32 which corresponds to
at least the right-end fastening portion 35a. Herein, a penetration
hole 36e for insertion of the bolt B4 is formed at a central
portion of one of the plural base portions 36cs which is provided
at the right end portion 3a.
[0090] Accordingly, as shown in FIG. 8B, in a state where the rear
underfloor member 3 is attached to the respective frames 9a, 8a, 8b
provided below the floor panel 4 from below, the height (H1) of
portions of an upper face of the rear underfloor member 3 which
correspond to the right-end fastening portion 35a, the left-end
fastening portion 35b, and the middle fastening portion 35c can be
set to be higher than the height (H2) of the other portion in the
vehicle width direction, similarly to the front underfloor member
2.
[0091] Moreover, since the concave central portion 31e (see FIG. 7)
is formed at the upper face of the central portion, in the plan
view, of the rear tunnel corresponding portion 31 of the rear
underfloor member 3, the height (H2) of the rigidity center g at
the central portion, in the vehicle width direction, of the rear
tunnel corresponding portion 31 can be set to be lower
accordingly.
[0092] Accordingly, the middle fastening portion 35c and the
left-end fastening portion 35b at the both ends, in the vehicle
width direction, of the rear tunnel corresponding portion 31 are
respectively fastened to the right tunnel side member 8a and the
left tunnel side member 8b at the level (H1) higher than the level
(H2) of the rigidity center g (gravity) of the rear tunnel
corresponding portion 31.
[0093] Thereby, even if the vehicle-side-collision load large
enough to deform the rear underfloor member 3 itself is inputted to
the rear underfloor member 3 from the vehicle-body rightward side,
similarly to the case of the front underfloor member 2, the rear
tunnel corresponding portion 31 which is configured to be deformed
with priority, compared with the rear auxiliary-device
corresponding portion 32, can be deformed so as to be bent downward
surely (see the rear tunnel corresponding portion 31 shown by an
imaginary line in FIG. 8B), thereby providing the similar effect to
the front underfloor member 2. Moreover, since the concave central
portion 31e is formed at the upper face of the central portion, in
the plan view, of the rear tunnel corresponding portion 31 of the
rear underfloor member 3, a vertical-directional space S1 formed
below the tunnel portion 4a which is configured such that the
height thereof becomes lower toward its rear side can be secured
even in a case where the rear tunnel corresponding portion 31 is
arranged below the tunnel portion 4a as shown in FIG. 4.
[0094] The lower vehicle-body structure of the automotive vehicle
of the above-described present embodiment comprises the floor panel
4 which has the tunnel portion 4a which extends in the longitudinal
direction at the center, in the vehicle width direction, of the
vehicle, the pair of right-and-left floor frames 9a, 9b which are
provided on the lower face of the floor panel 4 to interpose the
tunnel portion 4a between them, and the pair of right-and-left
tunnel side members 8a, 8b which extend along the tunnel portion 4a
at the respective positons which are located on the outward side,
in the vehicle width direction, of the tunnel portion 4a and on the
inward side, in the vehicle width direction, of the floor frames
9a, 9b, wherein the power storage unit 40 as the auxiliary device
is provided below the portion of the floor panel 4 which is
positioned between the floor frame 9a and the tunnel side member
8a, the underfloor members 2, 3 (the front underfloor member 2 and
the rear underfloor member 3) which extend in the vehicle width
direction and straddle the right floor frame 9a where the power
storage unit 40 is provided and the left tunnel side member 8b
which is opposite to the side where the power storage unit 40 is
provided are attached, and the yield strength of the vehicle width
direction of the tunnel corresponding portions 21, 31, in the width
direction, of the underfloor members 2, 3 which corresponds to the
tunnel portion 4a are set to be lower than that of the
auxiliary-device corresponding portions 22, 32, in the width
direction, of the underfloor members 2, 3 which correspond to the
power storage unit 40 (see FIGS. 1-3).
[0095] According to the above-described structure, even in a case
where the vehicle-side-collision load from the vehicle-body right
side where the power storage unit 40 is provided is applied to the
floor frame 9a which is apart inward from the right side sill 5a,
this collision load can be dispersed to the pair of right-and-left
tunnel side members 8a, 8b provided on the both sides of the tunnel
portion 4a. Further, even in a case where the
vehicle-side-collision load large enough to deform the underfloor
members 2, 3 is inputted from the vehicle-body right side, the
tunnel corresponding portions 21, 31 which have the lower
vehicle-width-directional yield strength than the auxiliary-device
corresponding portions 22, 23 can be deformed with priority,
thereby absorbing the collision load, and also the
power-storage-unit arrangement space S can be secured by the
auxiliary-device corresponding portions 22, 23.
[0096] Accordingly, the power-storage-unit arrangement space S can
be secured surely even in the vehicle side collision. Moreover,
since this power-storage-unit arrangement space S corresponds to an
arrangement position, in the vehicle width direction, of a front
seat 20, a survival space of a passenger can be secured.
[0097] In the embodiment of the present invention, the front
underfloor member 2 is configured such that the front tunnel
corresponding portion 21 and the front auxiliary-device
corresponding portion 22 are integrated, and the front
auxiliary-device corresponding portion 22 has the greater width, in
the longitudinal direction, than the front tunnel corresponding
portion 21 (see FIGS. 1 and 2).
[0098] According to the above-descried structure, the vehicle
height can be prevented from being improperly low and also the
productivity of the front underfloor member 2 and the covering
performance of the power storage unit 40 can be improved.
[0099] Specifically, since the front underfloor member 2 is
configured such that the front auxiliary-device corresponding
portion 22 is wider, in the longitudinal direction, than the front
tunnel corresponding portion 21 and extends in the vehicle width
direction from the right floor frame 9a to the left tunnel side
member 8b, the transmission and dispersion performances of the
vehicle-side-collision load can be improved. Accordingly, compared
with a case where the thick of the conventionally-exiting gusset
which is laid only between the right floor frame 9a and the right
tunnel side member 8a is made thicker in the vertical direction in
order to secure the strength, for example, the thickness of the
front underfloor member 2 can be properly thin, securing the
strength, so that it can be prevented that the minimum ground
clearance of the vehicle becomes improperly low.
[0100] Further, since the front auxiliary-device corresponding
portion 21 can be thin with the sufficient strength, the
workability of press forming or the like can be increased and
thereby the productivity can be improved, compared with the
conventionally-existing gusset which is configured to have a deep
concave portion or a high convex portion at its upper or lower face
for the sufficient strength.
[0101] Moreover, since the front auxiliary-device corresponding
portion 22 can cover the power storage unit 40 over a wide range in
the longitudinal direction, the protection performance
(auxiliary-device covering performance) of the power storage unit
40 against chipping by flying stones during the vehicle traveling
or the like can be improved.
[0102] Further, in the embodiment of the present invention, the
rear tunnel corresponding portion 31 of the rear underfloor member
3 has the front-side constricted portion 38a which is configured
such that the inward side, in the vehicle width direction, thereof
has the narrower width, in the longitudinal direction, than the
outward side, in the vehicle width direction, thereof, the rear
auxiliary-device corresponding portion 32 of the rear underfloor
member 3 is configured to substantially linearly extend along the
vehicle width direction, and the rear underfloor member 3 is
attached such that the rear auxiliary-device corresponding portion
32 is offset toward the constricted portion 38a of the rear tunnel
corresponding portion 31 in the longitudinal direction (see FIGS. 2
and 3).
[0103] According to the above-described structure, when the vehicle
has the side collision from the vehicle right side, the collision
load can be received jointly by the rear auxiliary-device
corresponding portion 32 and the rear tunnel corresponding portion
31 as described above. Further, when the large load is inputted,
the rear tunnel corresponding portion 31 having the front-side
constricted portion 38a can be deformed more preferentially than
the rear auxiliary-device corresponding portion 32 when receiving
the load from the rear auxiliary-device corresponding portion 32
configured to be offset forward, thereby absorbing the collision
load and dispersing the collision load to the left tunnel side
member 8b, and the power-storage-unit arrangement space S can be
secured by the rear auxiliary-device corresponding portion 32.
[0104] That, is, by configuring that the rear tunnel corresponding
portion 31 has at least one of the front-side constricted portion
38a and the rear-side constricted portion 38b, the rear tunnel
corresponding portion 31 can be made weak and thereby be
constricted in the vehicle width direction more preferentially than
the rear auxiliary-device corresponding portion 32 in the
right-side vehicle side collision, so that the rear tunnel
corresponding portion 31 can be deformed downward, thereby
absorbing the collision load.
[0105] Moreover, since the rear tunnel corresponding portion 31 can
be made to be deformed more easily for the load input by
configuring that the rear auxiliary-device corresponding potion 32
is connected so as to be offset, in the longitudinal direction,
toward the front-side constricted portion 38a of the rear tunnel
corresponding portion 31, this portion 31 is configured such that
its yield strength can be low, without making its
longitudinal-directional width smaller, its rigidity regarding the
vehicle-body rigidity can be high, and its strength against the
load input from the rear auxiliary-device corresponding portion 32
can be weak.
[0106] Also, in the present embodiment, since the rear tunnel
corresponding portion 31 is supported at the tunnel side members
8a, 8b provided at the right-and-left both sides of the tunnel
portion 4a from its both sides and formed in the butterfly shape in
the bottom view, that is, configured to have at least the X-shaped
convex portion 31a, the rigidity of the vehicle width direction of
the tunnel portion 4a can be increased by the rear tunnel
corresponding portion 31, thereby increasing the vehicle-body
rigidity in the normal vehicle traveling.
[0107] Moreover, in the embodiment of the present invention, the
power storage unit 40 is arranged on the right side of the tunnel
portion 41 only, and the left end portions 2b, 3b of the front and
rear underfloor members 2, 3 (the front underfloor member 2 and the
rear underfloor member 3) are connected to the left tunnel side
member 8b (see FIGS. 1 and 3).
[0108] According to the above-described structure, even in a case
where the vehicle has the side collision from the left side which
is opposite, relatively to the tunnel portion 4a, to the right side
where the power-storage-unit arrangement space S is provided, the
vehicle-side-collision load can be prevented from being transmitted
to the power-storage-unit arrangement space S via the front and
rear underfloor members 2, 3. Also, even in a case where the
collision load is inputted from the vehicle left side and this load
is transmitted to the front underfloor member 2 and/or the rear
underfloor member 3, the tunnel corresponding portions 21, 31 of
the front and rear underfloor members 2, 3 are deformed more
preferentially than the auxiliary-device corresponding portions 22,
32 and thereby absorb the vehicle-side-collision load, thereby
securing the power-storage-unit arrangement space S surely.
[0109] Further, as shown in FIGS. 1-4, in the present embodiment,
the front tunnel corresponding portion 21 and the front tunnel
cross member 100 are located at the same position in the
longitudinal direction. Meanwhile, the outward portions, in the
vehicle width direction, of the rear tunnel corresponding portion
31, that is, the front middle fastening portion 35cf and the front
left-end fastening portion 35b f are located at the same position,
in the longitudinal direction, as the rear tunnel cross member 101.
Thereby, the rigidity of the vehicle width direction of the tunnel
portion 4a is so increased that the vehicle-body rigidity in the
normal state can be increased.
[0110] The front tunnel corresponding portion 21 is located at the
same position, in the longitudinal direction, of the front tunnel
cross member 100 which is positioned above the front tunnel
corresponding portion 21, whereas the rear tunnel corresponding
portion 31 is provided to be rearward offset from the rear tunnel
cross member 101 which is positioned above the rear tunnel
corresponding portion 31 according to its being rearward offset
from the rear auxiliary-device corresponding portion 32 (see FIGS.
2 and 4). Herein, since the tunnel portion 4a is generally
configured such that the height thereof becomes lower toward its
rear side as shown in FIG. 4, the height of an inside (lower) space
of the tunnel portion 4a becomes gradually lower.
[0111] According to the present embodiment, meanwhile, since the
rear tunnel corresponding portion 31 is configured such that its
X-shaped central portion is offset rearward from the rear tunnel
cross member, as shown in FIG. 4, the rear underfloor member 3 is
located at the higher level than the minimum ground clearance H of
the vehicle, and also the vertical space S1 inside the tunnel
portion 4a which is positioned at the rear side of the tunnel
portion 4a is not narrowed by the rear tunnel corresponding portion
31 and the rear tunnel cross member 101 from upper, lower, left or
right sides, so that the layout property of the inside of the
low-height rear side of the tunnel portion 4a can be secured.
[0112] Moreover, in the present embodiment, the vehicle right side
of a portion which corresponds to a position of the floor panel 4
having the power-storage-unit arrangement space S is located at the
higher level than the vehicle left side of the above-described
portion (Hr<HI) (see FIG. 3). Thereby, the power-storage-unit
arrangement space S can be secured.
[0113] Herein, it is preferable in securing a foot space for a
passenger seated in a rear seat, not illustrated, that a structure
where part of the floor panel 4 is located at the high level as
described above be formed at a portion which is positioned in front
of the foot space and corresponds to a seat cushion portion 200a of
the front seat 200 among portions of the floor panel 4 which
correspond to the power-storage-unit arrangement space S in the
plan view.
[0114] There is a concern that the front and rear cross members
210, 211 which are provided on the upper-face side of the floor
panel 4 and the vehicle right side (see FIGS. 3, 5A and 5B) becomes
so thin that the rigidity against the vehicle-side collision may
become low by locating part of the floor panel 4 at the high level
as described above. According to the present embodiment, however,
the vehicle body is reinforced by the front and rear underfloor
members 2, 3 which are provided on the lower-face side of the floor
panel 4 at the positions which correspond to, in the longitudinal
direction, the front and rear cross members 210, 211, so that the
rigidity against the vehicle-side-collision load can be
secured.
[0115] As shown in FIGS. 5A and 5B, seat support brackets 212
(212a, 212b) are provided at both sides, in the vehicle width
direction, of the rear cross member 211. Each of these seat support
brackets 212a, 212b comprises a bracket upper portion 212U and a
bracket lower portion 212D which is thinner than the bracket upper
portion 212U, which are originally formed separately and joined
together finally to form each of the box-shaped seat support
brackets 212a, 212b.
[0116] It is preferable that the seat bracket 212a provided on the
side of the side sill 5 (the outward-side seat support bracket
212a) be configured such that a cutout portion 213 is formed at
front and rear wall portions of the bracket lower portion 212D as
shown in FIG. 5A. This cutout portion 213 is configured such that a
lower side portion of each wall portion of the bracket lower
portion 212D, including its lower end portion, is cutoff from an
outward end toward an inside.
[0117] By making the bracket lower portion 212D of the outward-side
seat support bracket 212a thin and forming the cutout portion 213
at the bracket lower portion 212D as described above, the
outward-side seat support bracket 212a itself can be made weak (the
yield strength of the vehicle width direction can be made low).
Thereby, the vehicle-side-collision load transmitted from the side
sill 5a can be absorbed by the outward-side seat support bracket
212a being deformed, so that the vehicle-body deformation caused by
the collision load can be kept up to the deformation of the
outward-side seat support bracket 212a. Thus, the
power-storage-unit arrangement space S which is positioned more
inward, in the vehicle width direction, from the outward-side seat
support bracket 212a can be protected from crushing.
[0118] Meanwhile, there is a concern that the seat support bracket
212 may not be able to secure the sufficient seat support rigidity
in a case where its whole part is configured to be weak. In the
present embodiment in which the bracket upper portion 212U is
configured to have the thinner thick than the bracket lower portion
212D, however, the seat load can be received by the bracket upper
portion 212U and dispersed to the bracket lower portion 212D
efficiently, so that the seat support rigidity can be increased as
a whole of the seat support bracket 212 with its light weight.
[0119] In correspondence between the present invention and the
above-described embodiment, the auxiliary device of the present
invention corresponds to the power storage unit 40 of the
embodiment. Likewise, the member corresponds to the front
underfloor member 2 or the rear underfloor member 3, the tunnel
corresponding portion corresponds to the front tunnel corresponding
portion 21 or the rear tunnel corresponding portion 31, the
auxiliary-device corresponding portion corresponds to the front
auxiliary-device corresponding portion 22 or the rear
auxiliary-device corresponding portion 32, and the constricted
portion corresponds to the front-side constricted portion 38a.
However, the present invention should not be limited to the
above-described embodiment.
[0120] For example, while the rear tunnel corresponding portion 31
of the present embodiment is configured in a central constricted
shape such that it has the front-side constricted portion 38a and
the rear-side constricted portion 38b, each of which is configured
such that the inward side, in the vehicle width direction, thereof
has the narrower width, in the longitudinal direction, than the
outward side, in the vehicle width direction, thereof, the present
invention is not limited to this but applicable to the rear tunnel
corresponding portion having either one of the above-described
constricted portions.
[0121] Further, the upper panel 33 of the rear tunnel corresponding
portion 31 may have the X shape in the bottom view similarly to the
lower panel 34 so that the rear tunnel corresponding portion 31
itself can provide the X-shaped contour in the bottom view. Thus,
by configuring the rear tunnel corresponding portion 31 to have at
least the X-shaped portion, the vehicle can be effectively
restrained from being twisted during the vehicle's normal
traveling.
[0122] Also, while the rear auxiliary-device corresponding portion
32 of the present embodiment is configured to have substantially
the same longitudinal width as the front auxiliary-device
corresponding portion 22, the present invention is not limited to
this configuration, and the above-described longitudinal width may
be set to be the same as or shorter than the longitudinal width of
the pair of right-and-left linear convex portions 31c, 31d which
constitute the X-shaped convex portion 31a of the rear tunnel
corresponding portion 31, for example, as long as the yield
strength of the vehicle width direction of the rear tunnel
corresponding portion 31 is set to be smaller than that of the rear
auxiliary-device corresponding portion 32.
[0123] Moreover, the present invention is not limited to the
structure in which the front underfloor member 2 and the rear
underfloor member 3 are provided below the floor panel 4, and
either one of the underfloor members may be provided so as to cover
the power storage unit 40 as the auxiliary device from below.
* * * * *